Oil well orienting apparatus



Aug. 11, 1953 M- A Q j "'j 44 i 22 1 J 29 507 3i 4- 9 52 w o a 52 7 .4 52 4. pl 2 51 i0 alexorzder b.HiZdebrc1r1dt SaverzLon b 1 Clbborneg Patented Aug. 11, 1953 n 2,648,141 OIL WELL ORIENTING APPARATUS Alexander B. Hildebrandt, Tulsa, Okla., assignor to Standard Oil Development Company, a corporation of Delaware Application June 5, 1948, Serial No. 31,367

The present invention relates to an apparatus to be employed in conjunction with a conventional device utilized in oil drilling operations, to determine the orientation of the device in the bore hole. In accordance with the present invention, a novel apparatus is lowered into a bore hole, the apparatus having at least one element which is normally maintained in a fixed orientation. The apparatus is designed and adapted to engage and hold an element of the conventional piece of equipment, locking the element of fixed orientation so that on withdrawing the apparatus to the surface, the orientation of the device in the bore hole will be indicated.

For many applications in oil well drilling it is necessary to know the exact orientation of a particular tool, or apparatus in the well. By orientation in this instance, and throughout this patent, reference is had asv to the azimuthal orientation; that is, in which direction of the compass a particular part of the apparatus, or device is directed. For example, a wire line coring apparatus may be lowered into a well bore hole to obtain a core sample at the bottom of the well. As the coring equipment is usually supported by a single cable, considerable twisting of the cable and hence rotation of the coring apparatus generally occurs so that it is normally impossible to know the actual orientation of the core in the Well when the core'is brought to the surface. In accordance'with the present invention, the determination of the orientation of the coring apparatus and the core is possible by employing the novel apparatus herein disclosed. The apparatus enables engagement with the core holder in a fixed orientation at the well bottom so that on pulling the entire apparatus to the surface of the earth, the orientation of the core barrel at the bottom of the bore hole will be known. As a further example of the application of this invention, it may be necessary to correct or to direct the inclination of a well bore hole which is being drilled. In order to do this, a so-called whipstock element may be lowered into the well. The whipstock is essentially a wedge-like block, which when properly oriented in the bore hole will deflect the drill bit in a manner to correct, or direct the inclination of the bore hole. Again, 'itis possible, by employing the apparatus of this invention to orient the Whipstocl: in the well so as to properly direct drilling operations.

As indicated, therefore, the principal object of this invention is to provide an apparatus for lowering into an oil well bore hole to determine 5 Claims. (01. 33205) the orientation of tools positioned in the bore 2 hole. This is accomplished by maintaining an engageable member of the orientation apparatus in a fixed azimuthal orientation by gyroscopic action. When the orientation apparatus ten 2 gages a core barrel or equivalent apparatus in the bore hole, or a detachable member of the apparatus in the bore hole, the weight of the apparatus or element engaged is operative to lock the engageable member in its orientation relative to the engaged element at the instant of engagement. On withdrawing the entire apparatus to the surface of the earth, the position of the tool in the oil well will then be indicated. The apparatus of this invention will be fully understood from the following description in con nection with the accompanying drawing illustrating a preferred embodiment of the present invention. Referring to the drawing, an embodiment of the apparatus of this invention is illustrated in cross-section elevational detail.

Referring now to the drawing, the numeral 29 designates an oil well bore hole which has been drilled in the earth. While the hole has been shown as an uncased hole, it is apparent that the hole may be cased if desired. Extending downwardly in the hole is a drill string II, which is conventionally used to support the drilling tools employed to drill the bore hole. A core sampler I0 is illustrated, which it is assumed has been dropped through the drill string to obtain a core at the bottom of the bore hole. In order to determine the orientation of the core sampler, and thus of the core within the sampler, the apparatus in the upper part of the drill string is employed. This apparatus comprises a liquid-tight housing 2| containing the elements illustrated. Positioned in the upper part of the apparatus is a yroscopic element indicated by the numeral I. This element is indicated diagrammatically and will not be described in great detail, as the gyroscopic element itself is not a part of this invention. Essentially the gyroscopic element comprises a universally mounted rotating wheel having a horizontal spin-axle. The natural turning of the spinaxle relative to the earth, due to the rotation of the earth, isneutralized by a precession of equal speed in the opposite direction produced by the weight of a small mass attached to the north bearing of the spin-axle.

The spin-axle is suitably connected to the housing of the gyro unit so that the housing will be maintained in in a vertical position determined by the position of the spin-axle. Thus, if the spin-axle is maintained in a North-South direction, due to the rotation of the gyro unit, reference markings on the housing of the gyroscope will similarly be maintained in the North-South direction. Gyroscopic elements of this. nature are well known to the art and are used, for example, in the Surwel Gyroscopic Clinograph, a description of which will be found in Applied Gyrodynamics, published by John Wiley and Sons, onpage 74. Similar gyroscopic units which may be adapted to the purposes of this invention may be found described in U. S. Patents 1,928,971 and 1,999,215. The only modifications of these devices necessary is that the housing of the gyroscope illustrated in Figure 1 be operated by the spin-axle of the gyroscope to remain in a fixed azimuthal orientation corresponding to that of the spin-axle. Thus shafts 4i and 42, connected to the casing of the gyroscopic element are rotatably supported in the bearings illustrated. If it be assumed that the gyroscope is started at the surface of the earth so that the spinaxle of the gyroscope is in a North-South direction, this arrangement will be suitable so that reference markings on the casing of the gyroscopic element rotatably supported by shafts 4| and 42 will remain in a North-South direction regardless of the rotation of the housing 2| of the apparatus. This may be checked when the gyroscope is started at the surface of the earth by sighting through the sight glass 3 to observe markings provided on the case of the gyroscopic element as illustrated. Sight glass 3 may be provided with vertical cross hairs to permit alignment with and reading of the reference marks on the gyro element. In the description which follows, therefore, it is to be understood that shaft 42 is normally maintained in a fixed azimuthal orientation. Thus, a particular line along the shaft 42 will, after the gyroscope is started, be maintained in a North direction. The lower part of shaft 42 terminates in an enlarged circular element 23 which may have a rough, high friction, surface on the upper surface thereof, or which may have geared teeth provided on it. These geared teeth, or the friction surface, are adapted to contact the underside of the bucket shaped element 24, having turned under edges for the purpose. The underside surfaces of element 24 will be provided with a friction surface, or with geared teeth corresponding to those provided on element 23. Therefore, when elements 23 and 24 are brought into contact with each other, the elements will tend to lock together preventing any relative rotation of the two parts. The bucket shaped element 24 is supported by a shaft 6 extending through a partition 43 provided in the casing of the apparatus. The shaft 6 is provided with splines, or equivalent means so as to prevent any rotation of this shaft 6, with respect to the partition 43. By virtue of this arrangement, circular element 23 connected to the shaft 42 controlled by the gyroscopic element will be maintained in a particular orientation as long as element 23 is free of the contact surface of element 24. Similarly, the element 24, by virtue of the splines on the shaft 6 supporting the element, will be maintained in an orientation corresponding to that of the case 2! in which the entire apparatus is placed. However, on contact of elements 23 and 24, the arrangement of parts described will cause the shaft 42, connected with the gyroscopic element, to become locked, so that thereafter the orientation position of shaft 42 will not be controlled by the gyroscopic element, but will be controlled by the orientation of the apparatus casing 2|. Therefore, the orientation of the apparatus, at the instant element 24 looks element 23, will be indicated by the relative positions of the reference markings on the gyroscopic element and the sight glass. The elements 23 and 24 described, therefore, essentially correspond to clutch elements designed to operate in two po- 4 sitions, in one of which the element 24 looks the gyroscopic element and in the other of which the gyroscopic element is permitted to be maintained in a constant orientation by the yroscopic action.

In order to control the engaged and disengaged positions of the clutch described, a spring I3 is provided, acting against a shoulder of the shaft 6 and against the lower part of the casing 2|. Spring l3 normally maintains the clutch in the disengaged position; that is, the spring l3 normally forces shaft 6 upwardly so as to prevent the contact surface of element 24 from contacting the contact surface of element 23. However, when shaft 6 is pulled downwardly against the action of the spring, the clutch will be engaged to lock shaft 42 and the gyroscopic element as described. In order to pull the shaft downwardly an enlarged section 30 is provided at the bottom of shaft 6. This enlarged section is provided with a cavity 3!, the opening of which cavity is partially blocked by the locking dogs 32. The cavity and locking dogs are of such a nature as to permit a spearhead 9 to enter the cavity and to hold the spearhead in the cavity. The arrangement is thus a locking device, permitting the element 30 to receive a spearhead 9 and to hold the spearhead. The cavity and spearhead are preferably provided with matching teeth or splines to prevent any rotation of the spearhead in the cavity. The spearhead 9 may be connected to, or made integral with an apparatus such as the core barrel IO positioned in the oil well. Consequently on engagement of the spearhead, the entire weight of the core barrel will be brought to bear on the locking dogs 32, when an upward force is applied on the supporting cable I2. The weight of the apparatus thus supported causes the shaft 6 to be pulled downwardly, causing engagement of the clutch elements as described. Locking teeth 21 may be provided on the shaft 6 to operate in conjunction with a latch 28, so that once shaft 6 is pulled downwardly the shaft is maintained in its lowermost position. A leaf spring 44 is provided to urge the locking member 28 against the locking teeth 21. It is apparent that in order to maintain the casing 2| watertight, packing 29 must be provided where the shaft 6 passes through the casing.

To summarize briefly, in the embodiment of this invention illustrated, a first clutch element within the casing of the apparatus is normally maintained in a fixed azimuthal orientation by the gyroscopic element. A second clutch element is maintained in an orientation corresponding to that of the case in which the apparatus is mounted. The clutch is caused to engage to lock the gyroscopic orientation element when a retrieving mechanism, attached to the shaft of the second clutch element, is brought in contact with, and caused to support the weight of a tool in the bore hole having a suitable spearhead. Consequently, when the gyroscopic element is started at the surface of the earth, prior to the orientation operation, and when the orientation of the gyroscopic unit has been checked through the sight glass provided, the apparatus may be lowered into a bore hole to engage an apparatus such as a core barrel within the bore hole. When the orientation apparatus is pulled upwardly after engagement with the core barrel, the gyroscopic element will be locked by the clutch device so that the orientation of the core barre1 will be indicated on pulling the entire apparatus to the surface of the earth.

The apparatus of this invention is adaptable for many applications. Clearly it is suitable for determining the orientation of any apparatus in a bore hole having sufficient inertia to actuate the locking device of the clutch. As indicated, to provide the necessary inertia to lock the clutch, the weight of the apparatus to be oriented may be employed. In this case, however, it is necessary to pull the orientation apparatus as well as the apparatus being oriented to the surface of the earth. While this is suitable for many applications, it is sometimes desired to leave the apparatus whose orientation is being determined at the bottom of the bore hole. In this case a simple expedient may be adopted. A suitable spearhead to be retained by the retrieving device of the orientation device will be attached to the apparatus to be oriented by a breakable pin. When the retrieving element of the orientation apparatus engages the spearhead, and when sufficient force is applied to break the pin, the clutch device will be locked, leaving the apparatus being oriented at the bottom of the well. This is illustrated in the drawing, wherein the core barrel I is shown to be composed of an upper element 50 having the spearhead 9, and the lower element 5| comprising the core barrel itself. Elements 50 and 5| are held together in a fixed relationship by the breakable pin 52, or by a plurality of such pins. These pins are so chosen that they may be broken by a force less than the weight of element 5|, but so as to require a breaking force greater than that required to lock the clutch. Therefore, when the spearhead 9 is pulled upward by the orienting apparatus sufficient force will be required to break the pins 52 to lock the clutch of the orientation apparatus. Normally, of course, this expedient for leaving the apparatus being oriented at the bottom of the bore hole would not be used for a core barrel. The expedient is of interest, for example, in the orientation of a whipstock to direct drilling procedures. The whipstock, comprising essentially a wedge shaped block, may be provided with the element 50 connected to the whipstock by suitable breakable pins. Reference markings will be placed on the whipstock and on the element 50. Therefore, when element 50 is pulled from the whipstock by the orientation apparatus, the orientation of the whipstock will be known when the element 50 is brought to the surface of the earth.

Having now fully described this invention, what is claimed is:

1. Oil well orientation apparatus comprising a housing, means for suspending said housing in a well, a first vertical shaft rotatably supported within said housing, a first clutch element fixed to said vertical shaft, a gyroscopic element connected to said first vertical shaft and adapted to maintain said first clutch element normally in a fixed azimuthal direction, a second vertical shaft slidably supported by said housing, fixed against rotation in said housing, and extending exterior of said housing, a second clutch element attached to said second shaft and engageable with said first clutch element upon sliding of said second shaft, a spring element normally urging said second shaft in a direction opposing engagement of said clutch elements, an engageable member attached to the exterior portion of said second shaft and adapted for lifting engagement with a body in the well whereby upon said engagement and upon exertion of a lifting force by said suspending means said clutch elements will engage.

2. Apparatus according to claim 1 including locking means adapted to hold said first and second clutch elements in engagement in opposition t the force exerted by said spring element.

3. Oil well orientation apparatus comprising a housing, means for suspending said housing in a well, a first vertical shaft rotatably supported within said housing, a first clutch element fixed to said shaft with an upwardly directed clutch face, a gyroscopic element connected to said first vertical shaft and adapted to maintain said first clutch element in a fixed azimuthal direction, a second vertical shaft slidably supported by said housing below said first shaft and fixed against rotation in said housing, said second shaft extending below said housing, a second clutch element attached to said second shaft, extending above said first clutch element but having a downwardly directed clutch face engageable with said first clutch face upon downward movement of said second shaft, a spring element normally urging said second shaft upwardly, and an enlarged section at the lower end of said second shaft below said housing, said enlarged section having a cavity adapted to receive a spearhead and with locking means for holding said spearhead in place in said cavity.

4. Apparatus according to claim 2 in which said second shaft is provided with looking teeth and in which said locking means adapted to hold said first and second clutch elements in engagement comprises a toothed latch pivotally attached to said housing and adapted to slide over said locking teeth when said second shaft is moved in a direction engaging said first and second elements and to engage said locking teeth to prevent the subsequent sliding of said second shaft in the opposite direction by the force exerted by said spring element.

5. Apparatus according to claim 1 in which said engageable member comprises an enlarged section at one end of said second shaft, said enlarged section being provided with a cavity adapted to receive a spearhead and with locking means for holding said spearhead in place in said cavity.

ALEXANDER B. I-IILDEBRANDT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 845,875 Lewis Mar. 5, 1907 908,299 Meine Dec. 29, 1908 1,124,068 Smitt Jan. 5, 1915 1,692,885 Brantly Nov. 27, 1928 1,803,785 Abler May 5, 1931 1,918,448 Box July 18, 1933 1,955,746 Inglis Apr. 24, 1934 2,000,524 Kothny May 7, 1935 2,182,534 Brandt Dec. 5, 1939 2,219,512 Cooper et a1. Oct. 29, 1940 2,283,720 Brandt May 19, 1942 2,405,717 Schadel Aug. 13, 1946 FOREIGN PATENTS Number Country Date 23,003 Great Britain 1908 

